Merge branch 'ioat' into fixes
[safe/jmp/linux-2.6] / drivers / dma / shdma.c
index 034ecf0..d10cc89 100644 (file)
 #include <linux/dmaengine.h>
 #include <linux/delay.h>
 #include <linux/dma-mapping.h>
-#include <linux/dmapool.h>
 #include <linux/platform_device.h>
 #include <cpu/dma.h>
 #include <asm/dma-sh.h>
 #include "shdma.h"
 
 /* DMA descriptor control */
-#define DESC_LAST      (-1)
-#define DESC_COMP      (1)
-#define DESC_NCOMP     (0)
+enum sh_dmae_desc_status {
+       DESC_IDLE,
+       DESC_PREPARED,
+       DESC_SUBMITTED,
+       DESC_COMPLETED, /* completed, have to call callback */
+       DESC_WAITING,   /* callback called, waiting for ack / re-submit */
+};
 
 #define NR_DESCS_PER_CHANNEL 32
 /*
@@ -45,6 +48,8 @@
  */
 #define RS_DEFAULT  (RS_DUAL)
 
+static void sh_dmae_chan_ld_cleanup(struct sh_dmae_chan *sh_chan, bool all);
+
 #define SH_DMAC_CHAN_BASE(id) (dma_base_addr[id])
 static void sh_dmae_writel(struct sh_dmae_chan *sh_dc, u32 data, u32 reg)
 {
@@ -80,17 +85,17 @@ static int sh_dmae_rst(int id)
        unsigned short dmaor;
 
        sh_dmae_ctl_stop(id);
-       dmaor = (dmaor_read_reg(id)|DMAOR_INIT);
+       dmaor = dmaor_read_reg(id) | DMAOR_INIT;
 
        dmaor_write_reg(id, dmaor);
-       if ((dmaor_read_reg(id) & (DMAOR_AE | DMAOR_NMIF))) {
+       if (dmaor_read_reg(id) & (DMAOR_AE | DMAOR_NMIF)) {
                pr_warning(KERN_ERR "dma-sh: Can't initialize DMAOR.\n");
                return -EINVAL;
        }
        return 0;
 }
 
-static int dmae_is_idle(struct sh_dmae_chan *sh_chan)
+static int dmae_is_busy(struct sh_dmae_chan *sh_chan)
 {
        u32 chcr = sh_dmae_readl(sh_chan, CHCR);
        if (chcr & CHCR_DE) {
@@ -106,19 +111,18 @@ static inline unsigned int calc_xmit_shift(struct sh_dmae_chan *sh_chan)
        return ts_shift[(chcr & CHCR_TS_MASK) >> CHCR_TS_SHIFT];
 }
 
-static void dmae_set_reg(struct sh_dmae_chan *sh_chan, struct sh_dmae_regs hw)
+static void dmae_set_reg(struct sh_dmae_chan *sh_chan, struct sh_dmae_regs *hw)
 {
-       sh_dmae_writel(sh_chan, hw.sar, SAR);
-       sh_dmae_writel(sh_chan, hw.dar, DAR);
-       sh_dmae_writel(sh_chan,
-               (hw.tcr >> calc_xmit_shift(sh_chan)), TCR);
+       sh_dmae_writel(sh_chan, hw->sar, SAR);
+       sh_dmae_writel(sh_chan, hw->dar, DAR);
+       sh_dmae_writel(sh_chan, hw->tcr >> calc_xmit_shift(sh_chan), TCR);
 }
 
 static void dmae_start(struct sh_dmae_chan *sh_chan)
 {
        u32 chcr = sh_dmae_readl(sh_chan, CHCR);
 
-       chcr |= (CHCR_DE|CHCR_IE);
+       chcr |= CHCR_DE | CHCR_IE;
        sh_dmae_writel(sh_chan, chcr, CHCR);
 }
 
@@ -132,7 +136,7 @@ static void dmae_halt(struct sh_dmae_chan *sh_chan)
 
 static int dmae_set_chcr(struct sh_dmae_chan *sh_chan, u32 val)
 {
-       int ret = dmae_is_idle(sh_chan);
+       int ret = dmae_is_busy(sh_chan);
        /* When DMA was working, can not set data to CHCR */
        if (ret)
                return ret;
@@ -149,7 +153,7 @@ static int dmae_set_dmars(struct sh_dmae_chan *sh_chan, u16 val)
 {
        u32 addr;
        int shift = 0;
-       int ret = dmae_is_idle(sh_chan);
+       int ret = dmae_is_busy(sh_chan);
        if (ret)
                return ret;
 
@@ -185,8 +189,9 @@ static int dmae_set_dmars(struct sh_dmae_chan *sh_chan, u16 val)
 
 static dma_cookie_t sh_dmae_tx_submit(struct dma_async_tx_descriptor *tx)
 {
-       struct sh_desc *desc = tx_to_sh_desc(tx);
+       struct sh_desc *desc = tx_to_sh_desc(tx), *chunk, *last = desc, *c;
        struct sh_dmae_chan *sh_chan = to_sh_chan(tx->chan);
+       dma_async_tx_callback callback = tx->callback;
        dma_cookie_t cookie;
 
        spin_lock_bh(&sh_chan->desc_lock);
@@ -196,45 +201,53 @@ static dma_cookie_t sh_dmae_tx_submit(struct dma_async_tx_descriptor *tx)
        if (cookie < 0)
                cookie = 1;
 
-       /* If desc only in the case of 1 */
-       if (desc->async_tx.cookie != -EBUSY)
-               desc->async_tx.cookie = cookie;
-       sh_chan->common.cookie = desc->async_tx.cookie;
+       sh_chan->common.cookie = cookie;
+       tx->cookie = cookie;
+
+       /* Mark all chunks of this descriptor as submitted, move to the queue */
+       list_for_each_entry_safe(chunk, c, desc->node.prev, node) {
+               /*
+                * All chunks are on the global ld_free, so, we have to find
+                * the end of the chain ourselves
+                */
+               if (chunk != desc && (chunk->mark == DESC_IDLE ||
+                                     chunk->async_tx.cookie > 0 ||
+                                     chunk->async_tx.cookie == -EBUSY ||
+                                     &chunk->node == &sh_chan->ld_free))
+                       break;
+               chunk->mark = DESC_SUBMITTED;
+               /* Callback goes to the last chunk */
+               chunk->async_tx.callback = NULL;
+               chunk->cookie = cookie;
+               list_move_tail(&chunk->node, &sh_chan->ld_queue);
+               last = chunk;
+       }
+
+       last->async_tx.callback = callback;
+       last->async_tx.callback_param = tx->callback_param;
 
-       list_splice_init(&desc->tx_list, sh_chan->ld_queue.prev);
+       dev_dbg(sh_chan->dev, "submit #%d@%p on %d: %x[%d] -> %x\n",
+               tx->cookie, &last->async_tx, sh_chan->id,
+               desc->hw.sar, desc->hw.tcr, desc->hw.dar);
 
        spin_unlock_bh(&sh_chan->desc_lock);
 
        return cookie;
 }
 
+/* Called with desc_lock held */
 static struct sh_desc *sh_dmae_get_desc(struct sh_dmae_chan *sh_chan)
 {
-       struct sh_desc *desc, *_desc, *ret = NULL;
+       struct sh_desc *desc;
 
-       spin_lock_bh(&sh_chan->desc_lock);
-       list_for_each_entry_safe(desc, _desc, &sh_chan->ld_free, node) {
-               if (async_tx_test_ack(&desc->async_tx)) {
+       list_for_each_entry(desc, &sh_chan->ld_free, node)
+               if (desc->mark != DESC_PREPARED) {
+                       BUG_ON(desc->mark != DESC_IDLE);
                        list_del(&desc->node);
-                       ret = desc;
-                       break;
+                       return desc;
                }
-       }
-       spin_unlock_bh(&sh_chan->desc_lock);
-
-       return ret;
-}
-
-static void sh_dmae_put_desc(struct sh_dmae_chan *sh_chan, struct sh_desc *desc)
-{
-       if (desc) {
-               spin_lock_bh(&sh_chan->desc_lock);
-
-               list_splice_init(&desc->tx_list, &sh_chan->ld_free);
-               list_add(&desc->node, &sh_chan->ld_free);
 
-               spin_unlock_bh(&sh_chan->desc_lock);
-       }
+       return NULL;
 }
 
 static int sh_dmae_alloc_chan_resources(struct dma_chan *chan)
@@ -253,11 +266,10 @@ static int sh_dmae_alloc_chan_resources(struct dma_chan *chan)
                dma_async_tx_descriptor_init(&desc->async_tx,
                                        &sh_chan->common);
                desc->async_tx.tx_submit = sh_dmae_tx_submit;
-               desc->async_tx.flags = DMA_CTRL_ACK;
-               INIT_LIST_HEAD(&desc->tx_list);
-               sh_dmae_put_desc(sh_chan, desc);
+               desc->mark = DESC_IDLE;
 
                spin_lock_bh(&sh_chan->desc_lock);
+               list_add(&desc->node, &sh_chan->ld_free);
                sh_chan->descs_allocated++;
        }
        spin_unlock_bh(&sh_chan->desc_lock);
@@ -274,7 +286,10 @@ static void sh_dmae_free_chan_resources(struct dma_chan *chan)
        struct sh_desc *desc, *_desc;
        LIST_HEAD(list);
 
-       BUG_ON(!list_empty(&sh_chan->ld_queue));
+       /* Prepared and not submitted descriptors can still be on the queue */
+       if (!list_empty(&sh_chan->ld_queue))
+               sh_dmae_chan_ld_cleanup(sh_chan, true);
+
        spin_lock_bh(&sh_chan->desc_lock);
 
        list_splice_init(&sh_chan->ld_free, &list);
@@ -293,6 +308,8 @@ static struct dma_async_tx_descriptor *sh_dmae_prep_memcpy(
        struct sh_dmae_chan *sh_chan;
        struct sh_desc *first = NULL, *prev = NULL, *new;
        size_t copy_size;
+       LIST_HEAD(tx_list);
+       int chunks = (len + SH_DMA_TCR_MAX) / (SH_DMA_TCR_MAX + 1);
 
        if (!chan)
                return NULL;
@@ -302,108 +319,189 @@ static struct dma_async_tx_descriptor *sh_dmae_prep_memcpy(
 
        sh_chan = to_sh_chan(chan);
 
+       /* Have to lock the whole loop to protect against concurrent release */
+       spin_lock_bh(&sh_chan->desc_lock);
+
+       /*
+        * Chaining:
+        * first descriptor is what user is dealing with in all API calls, its
+        *      cookie is at first set to -EBUSY, at tx-submit to a positive
+        *      number
+        * if more than one chunk is needed further chunks have cookie = -EINVAL
+        * the last chunk, if not equal to the first, has cookie = -ENOSPC
+        * all chunks are linked onto the tx_list head with their .node heads
+        *      only during this function, then they are immediately spliced
+        *      back onto the free list in form of a chain
+        */
        do {
-               /* Allocate the link descriptor from DMA pool */
+               /* Allocate the link descriptor from the free list */
                new = sh_dmae_get_desc(sh_chan);
                if (!new) {
                        dev_err(sh_chan->dev,
-                                       "No free memory for link descriptor\n");
-                       goto err_get_desc;
+                               "No free memory for link descriptor\n");
+                       list_for_each_entry(new, &tx_list, node)
+                               new->mark = DESC_IDLE;
+                       list_splice(&tx_list, &sh_chan->ld_free);
+                       spin_unlock_bh(&sh_chan->desc_lock);
+                       return NULL;
                }
 
-               copy_size = min(len, (size_t)SH_DMA_TCR_MAX);
+               copy_size = min(len, (size_t)SH_DMA_TCR_MAX + 1);
 
                new->hw.sar = dma_src;
                new->hw.dar = dma_dest;
                new->hw.tcr = copy_size;
-               if (!first)
+               if (!first) {
+                       /* First desc */
+                       new->async_tx.cookie = -EBUSY;
                        first = new;
+               } else {
+                       /* Other desc - invisible to the user */
+                       new->async_tx.cookie = -EINVAL;
+               }
 
-               new->mark = DESC_NCOMP;
-               async_tx_ack(&new->async_tx);
+               dev_dbg(sh_chan->dev,
+                       "chaining %u of %u with %p, dst %x, cookie %d\n",
+                       copy_size, len, &new->async_tx, dma_dest,
+                       new->async_tx.cookie);
+
+               new->mark = DESC_PREPARED;
+               new->async_tx.flags = flags;
+               new->chunks = chunks--;
 
                prev = new;
                len -= copy_size;
                dma_src += copy_size;
                dma_dest += copy_size;
                /* Insert the link descriptor to the LD ring */
-               list_add_tail(&new->node, &first->tx_list);
+               list_add_tail(&new->node, &tx_list);
        } while (len);
 
-       new->async_tx.flags = flags; /* client is in control of this ack */
-       new->async_tx.cookie = -EBUSY; /* Last desc */
+       if (new != first)
+               new->async_tx.cookie = -ENOSPC;
 
-       return &first->async_tx;
+       /* Put them back on the free list, so, they don't get lost */
+       list_splice_tail(&tx_list, &sh_chan->ld_free);
 
-err_get_desc:
-       sh_dmae_put_desc(sh_chan, first);
-       return NULL;
+       spin_unlock_bh(&sh_chan->desc_lock);
 
+       return &first->async_tx;
 }
 
-/*
- * sh_chan_ld_cleanup - Clean up link descriptors
- *
- * This function clean up the ld_queue of DMA channel.
- */
-static void sh_dmae_chan_ld_cleanup(struct sh_dmae_chan *sh_chan)
+static dma_async_tx_callback __ld_cleanup(struct sh_dmae_chan *sh_chan, bool all)
 {
        struct sh_desc *desc, *_desc;
+       /* Is the "exposed" head of a chain acked? */
+       bool head_acked = false;
+       dma_cookie_t cookie = 0;
+       dma_async_tx_callback callback = NULL;
+       void *param = NULL;
 
        spin_lock_bh(&sh_chan->desc_lock);
        list_for_each_entry_safe(desc, _desc, &sh_chan->ld_queue, node) {
-               dma_async_tx_callback callback;
-               void *callback_param;
-
-               /* non send data */
-               if (desc->mark == DESC_NCOMP)
+               struct dma_async_tx_descriptor *tx = &desc->async_tx;
+
+               BUG_ON(tx->cookie > 0 && tx->cookie != desc->cookie);
+               BUG_ON(desc->mark != DESC_SUBMITTED &&
+                      desc->mark != DESC_COMPLETED &&
+                      desc->mark != DESC_WAITING);
+
+               /*
+                * queue is ordered, and we use this loop to (1) clean up all
+                * completed descriptors, and to (2) update descriptor flags of
+                * any chunks in a (partially) completed chain
+                */
+               if (!all && desc->mark == DESC_SUBMITTED &&
+                   desc->cookie != cookie)
                        break;
 
-               /* send data sesc */
-               callback = desc->async_tx.callback;
-               callback_param = desc->async_tx.callback_param;
+               if (tx->cookie > 0)
+                       cookie = tx->cookie;
 
-               /* Remove from ld_queue list */
-               list_splice_init(&desc->tx_list, &sh_chan->ld_free);
+               if (desc->mark == DESC_COMPLETED && desc->chunks == 1) {
+                       BUG_ON(sh_chan->completed_cookie != desc->cookie - 1);
+                       sh_chan->completed_cookie = desc->cookie;
+               }
 
-               dev_dbg(sh_chan->dev, "link descriptor %p will be recycle.\n",
-                               desc);
+               /* Call callback on the last chunk */
+               if (desc->mark == DESC_COMPLETED && tx->callback) {
+                       desc->mark = DESC_WAITING;
+                       callback = tx->callback;
+                       param = tx->callback_param;
+                       dev_dbg(sh_chan->dev, "descriptor #%d@%p on %d callback\n",
+                               tx->cookie, tx, sh_chan->id);
+                       BUG_ON(desc->chunks != 1);
+                       break;
+               }
 
-               list_move(&desc->node, &sh_chan->ld_free);
-               /* Run the link descriptor callback function */
-               if (callback) {
-                       spin_unlock_bh(&sh_chan->desc_lock);
-                       dev_dbg(sh_chan->dev, "link descriptor %p callback\n",
-                                       desc);
-                       callback(callback_param);
-                       spin_lock_bh(&sh_chan->desc_lock);
+               if (tx->cookie > 0 || tx->cookie == -EBUSY) {
+                       if (desc->mark == DESC_COMPLETED) {
+                               BUG_ON(tx->cookie < 0);
+                               desc->mark = DESC_WAITING;
+                       }
+                       head_acked = async_tx_test_ack(tx);
+               } else {
+                       switch (desc->mark) {
+                       case DESC_COMPLETED:
+                               desc->mark = DESC_WAITING;
+                               /* Fall through */
+                       case DESC_WAITING:
+                               if (head_acked)
+                                       async_tx_ack(&desc->async_tx);
+                       }
+               }
+
+               dev_dbg(sh_chan->dev, "descriptor %p #%d completed.\n",
+                       tx, tx->cookie);
+
+               if (((desc->mark == DESC_COMPLETED ||
+                     desc->mark == DESC_WAITING) &&
+                    async_tx_test_ack(&desc->async_tx)) || all) {
+                       /* Remove from ld_queue list */
+                       desc->mark = DESC_IDLE;
+                       list_move(&desc->node, &sh_chan->ld_free);
                }
        }
        spin_unlock_bh(&sh_chan->desc_lock);
+
+       if (callback)
+               callback(param);
+
+       return callback;
+}
+
+/*
+ * sh_chan_ld_cleanup - Clean up link descriptors
+ *
+ * This function cleans up the ld_queue of DMA channel.
+ */
+static void sh_dmae_chan_ld_cleanup(struct sh_dmae_chan *sh_chan, bool all)
+{
+       while (__ld_cleanup(sh_chan, all))
+               ;
 }
 
 static void sh_chan_xfer_ld_queue(struct sh_dmae_chan *sh_chan)
 {
-       struct list_head *ld_node;
-       struct sh_dmae_regs hw;
+       struct sh_desc *sd;
 
+       spin_lock_bh(&sh_chan->desc_lock);
        /* DMA work check */
-       if (dmae_is_idle(sh_chan))
+       if (dmae_is_busy(sh_chan)) {
+               spin_unlock_bh(&sh_chan->desc_lock);
                return;
+       }
 
        /* Find the first un-transfer desciptor */
-       for (ld_node = sh_chan->ld_queue.next;
-               (ld_node != &sh_chan->ld_queue)
-                       && (to_sh_desc(ld_node)->mark == DESC_COMP);
-               ld_node = ld_node->next)
-               cpu_relax();
-
-       if (ld_node != &sh_chan->ld_queue) {
-               /* Get the ld start address from ld_queue */
-               hw = to_sh_desc(ld_node)->hw;
-               dmae_set_reg(sh_chan, hw);
-               dmae_start(sh_chan);
-       }
+       list_for_each_entry(sd, &sh_chan->ld_queue, node)
+               if (sd->mark == DESC_SUBMITTED) {
+                       /* Get the ld start address from ld_queue */
+                       dmae_set_reg(sh_chan, &sd->hw);
+                       dmae_start(sh_chan);
+                       break;
+               }
+
+       spin_unlock_bh(&sh_chan->desc_lock);
 }
 
 static void sh_dmae_memcpy_issue_pending(struct dma_chan *chan)
@@ -421,12 +519,11 @@ static enum dma_status sh_dmae_is_complete(struct dma_chan *chan,
        dma_cookie_t last_used;
        dma_cookie_t last_complete;
 
-       sh_dmae_chan_ld_cleanup(sh_chan);
+       sh_dmae_chan_ld_cleanup(sh_chan, false);
 
        last_used = chan->cookie;
        last_complete = sh_chan->completed_cookie;
-       if (last_complete == -EBUSY)
-               last_complete = last_used;
+       BUG_ON(last_complete < 0);
 
        if (done)
                *done = last_complete;
@@ -481,11 +578,13 @@ static irqreturn_t sh_dmae_err(int irq, void *data)
                err = sh_dmae_rst(0);
                if (err)
                        return err;
+#ifdef SH_DMAC_BASE1
                if (shdev->pdata.mode & SHDMA_DMAOR1) {
                        err = sh_dmae_rst(1);
                        if (err)
                                return err;
                }
+#endif
                disable_irq(irq);
                return IRQ_HANDLED;
        }
@@ -495,34 +594,25 @@ static irqreturn_t sh_dmae_err(int irq, void *data)
 static void dmae_do_tasklet(unsigned long data)
 {
        struct sh_dmae_chan *sh_chan = (struct sh_dmae_chan *)data;
-       struct sh_desc *desc, *_desc, *cur_desc = NULL;
+       struct sh_desc *desc;
        u32 sar_buf = sh_dmae_readl(sh_chan, SAR);
-       list_for_each_entry_safe(desc, _desc,
-                                       &sh_chan->ld_queue, node) {
-               if ((desc->hw.sar + desc->hw.tcr) == sar_buf) {
-                       cur_desc = desc;
-                       break;
-               }
-       }
 
-       if (cur_desc) {
-               switch (cur_desc->async_tx.cookie) {
-               case 0: /* other desc data */
-                       break;
-               case -EBUSY: /* last desc */
-               sh_chan->completed_cookie =
-                               cur_desc->async_tx.cookie;
-                       break;
-               default: /* first desc ( 0 < )*/
-                       sh_chan->completed_cookie =
-                               cur_desc->async_tx.cookie - 1;
+       spin_lock(&sh_chan->desc_lock);
+       list_for_each_entry(desc, &sh_chan->ld_queue, node) {
+               if ((desc->hw.sar + desc->hw.tcr) == sar_buf &&
+                   desc->mark == DESC_SUBMITTED) {
+                       dev_dbg(sh_chan->dev, "done #%d@%p dst %u\n",
+                               desc->async_tx.cookie, &desc->async_tx,
+                               desc->hw.dar);
+                       desc->mark = DESC_COMPLETED;
                        break;
                }
-               cur_desc->mark = DESC_COMP;
        }
+       spin_unlock(&sh_chan->desc_lock);
+
        /* Next desc */
        sh_chan_xfer_ld_queue(sh_chan);
-       sh_dmae_chan_ld_cleanup(sh_chan);
+       sh_dmae_chan_ld_cleanup(sh_chan, false);
 }
 
 static unsigned int get_dmae_irq(unsigned int id)
@@ -543,8 +633,8 @@ static int __devinit sh_dmae_chan_probe(struct sh_dmae_device *shdev, int id)
        /* alloc channel */
        new_sh_chan = kzalloc(sizeof(struct sh_dmae_chan), GFP_KERNEL);
        if (!new_sh_chan) {
-               dev_err(shdev->common.dev, "No free memory for allocating "
-                               "dma channels!\n");
+               dev_err(shdev->common.dev,
+                       "No free memory for allocating dma channels!\n");
                return -ENOMEM;
        }
 
@@ -586,8 +676,8 @@ static int __devinit sh_dmae_chan_probe(struct sh_dmae_device *shdev, int id)
                        "sh-dmae%d", new_sh_chan->id);
 
        /* set up channel irq */
-       err = request_irq(irq, &sh_dmae_interrupt,
-               irqflags, new_sh_chan->dev_id, new_sh_chan);
+       err = request_irq(irq, &sh_dmae_interrupt, irqflags,
+                         new_sh_chan->dev_id, new_sh_chan);
        if (err) {
                dev_err(shdev->common.dev, "DMA channel %d request_irq error "
                        "with return %d\n", id, err);
@@ -676,6 +766,8 @@ static int __init sh_dmae_probe(struct platform_device *pdev)
        shdev->common.device_is_tx_complete = sh_dmae_is_complete;
        shdev->common.device_issue_pending = sh_dmae_memcpy_issue_pending;
        shdev->common.dev = &pdev->dev;
+       /* Default transfer size of 32 bytes requires 32-byte alignment */
+       shdev->common.copy_align = 5;
 
 #if defined(CONFIG_CPU_SH4)
        /* Non Mix IRQ mode SH7722/SH7730 etc... */
@@ -688,8 +780,8 @@ static int __init sh_dmae_probe(struct platform_device *pdev)
        }
 
        for (ecnt = 0 ; ecnt < ARRAY_SIZE(eirq); ecnt++) {
-               err = request_irq(eirq[ecnt], sh_dmae_err,
-                       irqflags, "DMAC Address Error", shdev);
+               err = request_irq(eirq[ecnt], sh_dmae_err, irqflags,
+                                 "DMAC Address Error", shdev);
                if (err) {
                        dev_err(&pdev->dev, "DMA device request_irq"
                                "error (irq %d) with return %d\n",